The present invention relates to double-hung window assemblies and particularly to such windows having pivotally mounted sashes.
Pivoting sashes have become quite common in double-hung window assemblies as they have the usual advantage of being able to be raised and lowered as well as the special advantage of being tiltable to make cleaning of the window pane easier. Attention is directed to U.S. Pat. No. 4,581,850 which illustrates a double hung pivotal window assembly. While the structure of this patent and other similar commercial double hung pivoting assemblies have overcome many of the disadvantages of the prior window assemblies, several disadvantages still exist.
For example, a problem still arises where, during manufacturing and installation of the conventional assemblies, a "belly band" or similar elastic constriction must be used to maintain the assembly together so that the assembly remains truly square when installed in the window opening. Such "belly bands" while necessary, are a particular nuisance during transport and storage, since they must be kept in place during and after installation.
Another disadvantage occurs as a result of the inability to mount the sash to the sash frame, so that binding and warping of the sash frame are prevented. Still another problem arises out of the inability of locking the pivot sash in an open position so as to remove any stress on the pivot joint caused by its weight.
It is the object of the present invention to provide an improved pivotal sash assembly to overcome the aforementioned disadvantages as well to provide numerous other advantages will be obvious to persons skilled in the art from contemplation of the following disclosure.